This invention relates to a governor for a small size vehicle and more particularly to an improved and simplfied governor arrangement for an internal combustion engine.
There are many instances wherein it is desirable to run an internal combustion engine at a constant or governed speed. For example, if the engine forms a component of a vehicle that is utilized both for powering the vehicle and for driving accessories from the vehicle, it is desirable to provide a governor for the engine so that the engine will run at a preset speed when driving the power takeoff. For example, there have recently been proposed a class of small single rider vehicles which may be utilized for recreational or work purposes. In connection with the work purposes, such machines may be utilized to drive lawnmowers, water sprinklers or the like. When driving such accessories, it is desirable to insure that the engine is run at a constant speed.
Most mechanical governors employed with such small internal combustion engines are driven off of the engine crankshaft or in proximity to the engine crankshaft. The governor has an output element which is connected to a throttle valve in the engine for controlling the engine speed. Because the induction system is normally positioned at the cylinder head and remotely from the crankshaft, it is necessary to provide a linkage system wherein the governor output element is operative to control the remotely positioned throttle valve. Such an arrangement has a number of disadvantages. Where the vehicle is of the type that is adapted to be operated in off the road conditions, as in the applications as aforenoted, the linkage system is disposed at a relatively low area in the vehicle wherein it can be easily damaged by driving through rough terrain and terrain in which there is foliage which can strike the linkage. In addition, such low placement for the linkage puts it in an area where it can easily become damaged or encrusted with water or other foreign material due to the terrain over which the vehicle operates. In addition, the length of the linkage system employed with this type of device, in itself, can give rise to problems.
It is, therefore, a principal object of this invention to provide an improved governor mechanism for an internal combustion engine.
It is a further object of this invention to provide an engine governor wherein the governor is located in close proximity to the automatic speed controlling element which it operates.
It is a further object of this invention to provide an improved off the road vehicle and governor mechanism for it.
In connection with vehicles of the type described, it is frequently the case that the engine is utilized to propel the vehicle through a first transmission and drives a power takeoff shaft through another transmission. A clutching mechanism is emloyed for selectively driving either the power takeoff or the vehicle. When the vehicle itself is driven, it is the normal practice to permit the operator to control the speed of the engine so as to insure good stability and so that the operator can control the speed of the vehicle as conditions change. On the other hand, when the power takeoff is driven, it has been the normal practice to permit the governor to control the engine speed. Therefore, such a mechanism must employ an arrangement for shifting between governor controlled speed and operator controlled speed. This has been done, with prior art mechanisms, by providing a clutching mechanism between the engine driving shaft and the governor input shaft for selectively controlling the governor operation. However, such arrangements require a clutch for selectively driving the governor which must carry substantial loads and also to insure good shifting and positive drive. Therefore, prior art devices of this type have been relatively heavy and expensive.
It is, therefore, a further object of this invention to provide an improved and simplified arrangement for shifting between manual and automatic speed control.
It is a yet further object of this invention to provide a governor control mechanism for an internal combustion engine wherein the governor is driven continuously but is selectively operable to drive the automatic speed control element.